<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .tudou {
            position: relative;
            width: 432px;
            height: 240px;
            margin: 100px auto;
        }
        .mask {
            display: none;
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, .7);
        }
        .tudou .pic {
            width: 100%;
            height: 100%;
        }

        .tudou .play {
            display: none;
            position: absolute;
            top: 0;
            left: 0;
            bottom: 0;
            right: 0;
            margin: auto;
            width: 10%;
            height: 15%;
            border-radius: 50%;
        }
        .tudou:hover .mask, .play {
            display: block;
        }

    </style>
</head>
<body>
    <div class="tudou">
        <div class="mask"></div>
        <img src="img/play.png"  class="play" alt="">
        <img src="img/pic.jpg" class="pic" alt="">
    </div>
</body>
</html>